Air bladder suspension system for three-wheeled vehicle

ABSTRACT

An air bladder suspension system for a three-wheeled motorcycle is disclosed herein. The air bladders may be used alone or in combination with an existing suspension system and are positioned between the rear axle housing and rear frame of the three-wheeled motorcycle.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to suspension systems for three-wheeledmotorized vehicles, more particularly an air bladder suspension system.

[0003] 2. Prior Art

[0004] On most two- and three-wheeled motorcycles, conventionalsuspension systems provide a smooth ride to the operator. Theseconventional suspension systems often comprise spring- or air-loadedshocks that connect the frame and the axle. Problems arise, however,when a heavy operator (and perhaps a heavy passenger) sits on themotorcycle. Most conventional suspension systems are not equipped tohandle this increased weight and cannot effectively provide a smoothride. When the motorcycle encounters potholes or bumps, conventionalsuspension systems cannot handle the increased weight of the operatorand passenger, causing the motorcycle to “bottom out.”

ADVANTAGES AND OBJECTS OF THE INVENTION

[0005] The present invention provides advantages over conventionalsuspension systems. By using the present invention in combination withan existing conventional suspension system, the three-wheeled motorcyclehas an increased weight capacity without concerns that the motorcyclemay bottom out. The design of the present air-bladder system allows theamount of air or other fluid in the bladder to vary so that the bladdercan adjust to the desires of different users. This design also allows auser to adjust the amount of air in the bladder(s) to provide optimumriding conditions on any type of road conditions. The use of thespecially designed brackets allows quick and efficient positioning ofthe bladder(s) between the rear frame and the rear axle housing wheremost of the weight must be distributed.

[0006] With the aforementioned considerations in mind, it is thereforean object of this invention to provide an improved suspension system forthree-wheeled motorcycles.

[0007] It is a further object of this invention to provide anair-bladder suspension system that may be used in combination with aconventional suspension system.

[0008] It is a further object of this invention to provide an adjustableair-bladder suspension system.

[0009] It is a further object of this invention to provide an improvedsuspension system that allows heavier motorcycle operators to ride athree-wheeled motorcycle without concerns about the motorcycle bottomingout.

[0010] These and other advantages and objects of this invention shallbecome apparent from the ensuing description of the invention.

SUMMARY OF THE INVENTION

[0011] The invention disclosed herein is a three-wheeled motor vehiclecomprising (a) a rear axle housing operatively connectable to a pair ofrear wheels, (b) a rear frame connected to the existing frame of thethree-wheeled motor vehicle; and, (c) at least one inflatable airbladder operatively positioned between the rear axle housing and therear frame.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 illustrates a rear view of the rear frame attached to therear axle housing using the air-bladder suspension system.

[0013]FIG. 2 illustrates a top view of the air-bladder suspension systemshown along the 2-2 axis shown in FIG. 1.

[0014]FIG. 3 illustrates a close-up rear view of the air-bladderinvention.

[0015]FIG. 3a illustrates a partial side view of the rear portion of athree-wheeled motor vehicle incorporating both shock absorbers and airbladders.

[0016]FIG. 4 illustrates a side view of an air bladder.

[0017]FIG. 5 illustrates a side view of a lower bracket.

[0018]FIG. 6 illustrates a top view of a lower bracket.

[0019]FIG. 7 illustrates a side view of an upper bracket.

[0020]FIG. 8 illustrates a top view of an upper bracket.

[0021]FIG. 9 illustrates side views of the fittings that connect to thefitting on the air bladder.

[0022]FIGS. 10a-10 c illustrate an air bladder suspension systemincorporating a single air bladder and a sway bar.

DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

[0023] Illustrations of construction, design, and methods of operationof the invention are set forth below with specific references to theFigures. However, it is not intended that the scope of the invention belimited to these embodiments.

[0024] As shown in FIG. 1, rear frame 103 attaches to rear axle housing101 using the air bladder invention 102 positioned on both the left 198and right side 199 of rear axle housing 101, or other fixed point onaxle assembly 197. Rear axle housing 101 may comprise a single or dualaxle. As discussed below and shown in FIG. 3a, a shock absorber 300 isalso preferably connected between rear frame 103 and rear axle housing101. Referring back to FIG. 1, rear frame 103 may comprise a singlepiece or may comprise multiple interconnected components, such as alower member 121, an upper member 120 and a cross member 122. Airbladders 102 connect to rear axle housing 101 using lower brackets 109and connect to rear frame 103 using upper brackets 106.

[0025] Referring to FIG. 4, air bladder 102 comprises a compressibletubular member having a sealed upper end 123 and a sealed lower end 124and at least one compressible sidewall 125 defining an interior volumetherein. Lower end 124 is configured to receive a bolt 113, or otherconnecting member, that allows air bladder 102 to attach to lowerbrackets 109 via aperture 116 (shown in FIG. 6). Upper end 123 has astem 112 attached thereto or configured as part thereof.

[0026] Viewing FIG. 2, there are illustrated two rear wheels 115 and afront wheel 200 connected to an existing motorcycle frame 250 (shown indashed lines). An air fitting 114, connectable to L-shaped fitting 119(see FIG. 3a) as discussed below, is positioned within stem 112 as seenin FIG. 2. Viewing FIG. 4, stem 112 has a threaded exterior 108 thatallows air bladder 102 to attach to upper brackets 106 via aperture 117(shown in FIG. 8) using a nut 110 or other suitable means. Air fitting114 comprises an inlet-outlet aperture extending therethrough which hasa check valve positioned therein biased in a normally closed position toallow air bladder 102 to be inflated and deflated. Stem 112 and airfitting 114 are configured so that nut 110 does not restrict access tofitting 114 using L-shaped fitting 119 (shown in FIG. 9) when airbladder 102 is attached to upper bracket 106.

[0027] Air bladders 102 are preferably sleeved air springs availablefrom Air Lift Co. of Lansing, Mich. or Goodyear Tire and Rubber Companyof Akron, Ohio. Either of the following models is acceptable: Model No.58182 1S3-011 Maximum inflated diameter (inches) 4.6 3.6 Minimum height(inches) 2.2 3.6 Maximum height (inches) 7.1 8.0 Load @ 100 psi (poundsper square 880 415 inch)

[0028] Each model is preferably constructed with a ⅛-inch air fitting114.

[0029] Upper brackets 106, as shown in FIGS. 7 and 8, may comprise aplate 130 having a gusset 131 attached thereto. An aperture 117 isconfigured within plate 130 to allow stem 112 to extend through plate130 so that air bladder 102 attaches to upper bracket 106. Plate 130 hascurved portion 132 that engages frame 103 so that upper bracket 106connects to rear frame 103, such as by welding. Surface 123 a of airbladder 102 and surface 106 a of upper bracket 106 are both configuredto be substantially planar to provide a tight connection between airbladder 102 and upper bracket 106.

[0030] Lower brackets 109, as shown in FIGS. 5 and 6, comprise a lowerplate 134 having an aperture 116 extending therethrough to allow bolt113 to extend therethrough to attach air bladder 102 to lower bracket109. Lower bracket 109 also comprises a lower bracket gusset 135 havinga curved portion 136 that allows lower bracket 109 to engage and attachto the lower side of rear axle housing 101 by welding or other suitablemeans. Alternatively, lower brackets 109 may be constructed fromsuitable channeled-angle-iron material. Surface 109 a of lower bracket109 and surface 124 a of air bladder 102 are both configured to besubstantially planar to provide a substantially tight engagement betweenair bladder 102 and upper bracket 106.

[0031] Viewing FIGS. 1 and 2, air bladders 102 are positioned on eitherside of the center point of rear axle housing 101. Air bladders 102 maybe symmetrically, preferably substantially equidistant from differential400. Preferably, air bladders 102 are positioned no more than about 6inches, preferably about 1.5 inches, from the inner edge 115 a of wheels115 as shown in FIG. 2.

[0032]FIG. 3a illustrates a side view of a portion of three-wheeledmotorcycle incorporating the present invention. For clarity, wheels 115are shown removed from rear axle housing 101. An air shock absorber 300,or other conventional shock absorber, attaches between frame 103 andrear axle housing 101. The lower end of air shock absorber 300 attachesto a bolt extending forward from rear axle housing 101, and the upperend of air shock 300 suitably attaches to frame 103.

[0033] Air shock absorber 300 is preferably positioned forward of rearaxle housing 101. Air bladders 102 attach between rear frame 103 andrear axle housing 101. Air bladders 102 are positioned behind rear axlehousing 101, although air bladder 102 may be positioned forward of rearaxle housing 101 in other embodiments not shown in the Figures.

[0034] Though not shown in all Figures, each embodiment disclosed hereinalso incorporates an air line 301 connected to air bladder(s) 102 and/orair shock absorbers 300. The air lines 301 are connected and configuredas described below.

[0035] Viewing FIG. 3a, an air line 301 extends from a source ofcompressed air, such as an on-board air compressor 275, to air shock 300and air bladders 102. This allows the pressure within air bladder 102and/or air shock absorber 300 to be adjusted after air bladder 102 andshocks 300 have been installed on the motorcycle.

[0036] Air line 301 extends from the source of compressed air intoT-shaped fitting 118. From T-shaped fitting 118, airline 301 a extendsinto air shock 300, and airline 301 b connects to L-shaped fitting 119.For example, if a heavier rider wishes to ride the three-wheeledmotorcycle, it may be necessary to increase the air pressure within airbladders 102. On the other hand, if air bladder(s) 102 areover-inflated, the ride will feel stiff and bumpy. Thus, it may benecessary to deflate air bladder 102 to a desired pressure. Air lines301 may also be independently connected to air shock absorber 300 and/orair bladder(s) 102, allowing independent adjustment of the airsuspension components.

[0037] A two air bladder system installs onto a three-wheeled motorcycleas follows. The three-wheeled motorcycle is positioned on a centerstand, the rear tires are removed, and the battery is disconnected toavoid shorting any of the motorcycle's electrical components. Lowerbrackets 109 connect to rear axle housing 101, such as by welding,preferably about 1.5 inches from the inner edge 115 a of wheels 115. Adeflated air bladder 102 is positioned onto lower bracket 109. Bolt 113is the inserted through aperture 116 and loosely engaged with lower end124. Upper bracket 106 is positioned over air bladder 102 by insertingstem 112 through aperture 117 in upper bracket 106. Upper bracket 106 ispositioned such that the distance between upper bracket 106 and lowerbracket 109 is equal to the fully inflated length of air bladder 102.Upper bracket 106 is welded to frame 103. Nut 110 loosely engages stem112, which is positioned through aperture 117. This positioning of upperbracket 106 during installation allows air bladder 102 to be inflatedwithout raising the rear end of the motorcycle or making the ride toostiff with only minimum air pressure within bladder(s) 102.

[0038] In some embodiments, rear frame 103 may already be equipped withgussets 131. In such embodiments, upper bracket 106 comprises only plate130, which is welded to gusset 131 during installation.

[0039] L-shaped fitting 119 is then attached to air fitting 114 of airbladder 102, and air line 301 b is connected between L-shaped fitting119 and T-shaped fitting 118, which is preferably positioned near airshock 300. Air line 301 b connects between T-shaped fitting 118 and airshock 300. Air line 300 connects between T-shaped fitting 118 and asource of compressed air. This configuration allows air shocks 300 andair bladder 102 to operate using the same air system. Nuts 110 and bolts113 are tightened to provide a substantially tight fit between brackets106, 109 and air bladder 102.

[0040] Recommended air pressures in each air bladder 102 for a two- airbladder system are as follows: 1 Person  0-7 psi 2 Persons  7-21 psiWith a trailer 15-30 psi

[0041]FIGS. 10a-10 c illustrate an embodiment incorporating a single airbladder 102. This embodiment comprises an air bladder 102 connectedbetween rear axle housing 101 at differential 400 (or othersubstantially fixed central point or axle assembly 197) and frame 103 atcross member 122. The single air bladder embodiment is constructed asfollows.

[0042] Viewing FIGS. 10a-10 c, the three-wheeled motorcycle ispreferably constructed with left and right ladder bar supports 401, 402having center reinforcement bar 403 extending therebetween. Supports401, 402 connect to differential 400, preferably by welding. Referringto FIG. 10a, base plate 404, which has a ½-inch hole drilledtherethrough is welded between supports 401, 402 to provide a shelf uponwhich air bladder 102 is positioned. Bolt 113 inserts through the ½-inchhole in base plate 404 and loosely engages lower end 124 of air bladder102.

[0043] Top plate 806, which is constructed similarly to lower plate 109,connects to cross member 122, preferably by welding. Top plate 806 has ahole therein to allow stem 112 to extend therethrough and allows nut 110to engage stem 112, connecting air bladder 102 to top plate 806.

[0044] A suitable gusset 807 is welded between top plate 806 and upperframe member 120 to provide additional support and stability to the rearof the motorcycle. A suitable sway bar 808, available from Motor Trikeof Troup, Tex., connects between differential 400 and rear frame 103 tostabilize the rear frame and ensure a comfortable ride for the operator.Nut 100 and bolt 113 are tightened, air shock absorber(s) 300 (ifapplicable) and air bladder 102 are properly inflated, and installationof the air bladder suspension system is complete.

[0045] As discussed previously, air bladder 102 connects to a source ofcompressed air using L-shaped fitting 119 and an air line. The air linemay also connect with an air shock which has not been shown in FIGS.10a-10 c but will connect between frame 103 and rear axle housing 101 aspreviously described.

[0046] Although the preferred embodiment has been described, it will beappreciated by those skilled in the art to which the present inventionpertains that modifications, changes, and improvements may be madewithout departing from the spirit of the invention defined by theclaims.

We claim:
 1. A three-wheeled motor vehicle comprising: a rear axleassembly operatively connectable to a pair of rear wheels; a rear frameconnected to the existing frame of said motor vehicle; and, at least oneinflatable air bladder operatively positioned between said rear axleassembly and said rear frame.
 2. The vehicle according to claim 1wherein said air bladders comprise a tubular member having closed endsdefining an interior volume, said tubular member having collapsiblesidewalls.
 3. The vehicle according to claim 2 further comprising afitting attached to said bladder having a passageway therethrough sothat the pressure within said air bladder may be adjusted.
 4. Thevehicle according to claim 2 further comprising a first bracketattaching said air bladder to said rear frame.
 5. The vehicle accordingto claim 3 further comprising a second bracket attaching said airbladder to said rear axle assembly.
 6. The vehicle according to claim 3comprising two air bladders positioned between said rear frame and saidrear axle assembly.
 7. The vehicle according to claim 6 wherein saidbladders are positioned ahead of said rear axle assembly.
 8. The vehicleaccording to claim 6 wherein said bladders are positioned behind saidrear axle assembly.
 9. The vehicle according to claim 2 furthercomprising at least one shock absorber connected between said rear axleassembly and said rear frame.
 10. The vehicle according to claim 9further comprising a source of compressed air in fluid communicationwith said at least one air bladder.
 11. The vehicle according to claim 2further comprising a source of compressed air in fluid communicationwith said at least one air bladder.